An image pickup lens unit assembled into, for example, a mobile phone has a structure to retain a periphery of an optical lens for imaging by a holder. Significantly high positioning accuracy needs to be ensured in assembling the optical lens into the holder and, therefore, such an assembling is typically performed by using an automatic assembling system which has adopted an image recognition technique. Such a system, however, is very expensive and requires a very large area to configure a manufacturing line in which an insertion process for inserting the lens in the holder, a bonding process for bonding the lens to the holder, and the like are provided separately. Therefore, replacement of the equipment performed each time when the kind or type of lens is changed becomes large in scale and requires increased numbers of work steps.
As a manufacturing method for solving such problems, a technique to collectively assembling an image pickup lens unit by, after placing and positioning a lens and a diaphragm within a mold in advance with reference to an outer edge of the lens, forming a holder by injection molding on the periphery of the lens and the like is known (see Patent Literature 1).
In the manufacturing method of Patent Literature 1, however, in a case in which a lens diced from a wafer level lens is used, the following problem occurs: since a degree of eccentricity of an outer edge of the lens and an optical surface depends on the dicing precision of the wafer level lens, if misalignment (or eccentricity) is caused between the outer edge of the lens and the optical surface, it is difficult to obtain satisfactory optical performance.